Let's just say i want to a buy a rug and it says how many would you like to buy i put in x amount then i receive x amount in my inventory? I believe it would done by input I'm quite sure of that. But would i need the use of isnum etc?
Edit:
Right this could be incredibly wrong but its how i thought it may go? Also not to sure how i would then give x amount of the item after inputting.
mob/verb/giveme()
x = input("X","X",isnum(x))
There are many ways on giving someone items, but you generally will want to use a loop of some sort.
If you have anything that prevents players from carrying too many items, or carrying specific items, you will have to validate before doing this.